Mar 13, 2026 • Leetcode
Construct Quad Tree
Given a n * n matrix grid of 0's and 1's only. We want to represent grid with a Quad-Tree.
Read more →Recent Articles
Mar 12, 2026 • Leetcode
House Robber II
You are a professional robber planning to rob houses along a street.
Read more →Mar 11, 2026 • Leetcode
Two Sum II - Input Array Is Sorted
Given a 1-indexed array of integers numbers that is already sorted in non-decreasing order,
Read more →Mar 10, 2026 • Leetcode
Rotate Function
You are given an integer array nums of length n.
Read more →Mar 09, 2026 • Codeforces
New Year and Naming
Happy new year! The year 2020 is also known as Year Gyeongja (경자년, gyeongja-nyeon) in Korea. Where did the name come from?
Read more →Mar 09, 2026 • Leetcode
Wiggle Subsequence
A wiggle sequence is a sequence where the differences between successive numbers strictly alternate between positive and negative
Read more →
